Predictability of the power output of three wave energy technologies in the Danish North Sea

Abstract The paper addresses an important challenge towards the integration of the electricity generated by wave energy converters into the electric grid. Particularly, it looks into the role of wave energy within day-ahead electricity markets. For that the predictability of the theoretical power outputs of three wave energy technologies in the Danish North Sea are examined. The simultaneous and co-located forecast and buoy-measured wave parameters at Hanstholm, Denmark, during a non-consecutive autumn and winter 3-month period form the basis of the investigation. The objective of the study is to assess the accuracy of the forecast of (i) wave parameters, (ii) the normalised theoretical power productions of the selected technologies (Pelamis, Wave Dragon and Wavestar), and (iii) the normalised theoretical power production of a combination of the three converters, during a very energetic time period. Results show that the errors in day-ahead predictions (in terms of scatter index) of the significant wave height, zero crossing period and wave power are 22%, 11% and 74%, respectively; and of the normalised theoretical power outputs of Pelamis, Wave Dragon and Wavestar are 37%, 39% and 54%, respectively. The best compromise between forecast accuracy and mean power production results when considering the combined production of the three converters